1. Field of the Invention
The present invention relates to a silver halide light-sensitive material and, more particularly, it relates to a light-sensitive material in which fog occurs to a lesser extent.
2. Description of the Prior Art
As a method for rapidly processing light-sensitive materials, it is known to develop at an elevated temperature. In recent years, this method has been applied to the processing of various light-sensitive materials with some success. However, in general, development of light-sensitive materials at an elevated temperature tends to cause fog, which deteriorates the photographic quality. (The term "elevated temperature" as used herein means a temperature of at least about 30.degree.C up to about 45.degree.C.) In particular, when a developer containing a hardening substance (e.g., glutaraldehyde, etc.), such as a commercially available developer for rapidly processing X-ray films, is used, films sometimes are seriously fogged by the developer, especially when the developer is exhausted or fatigued (i.e., when the amount of films processed approaches almost the limit of the processing capability of the developer).
In general, the photographic sensitivity of a silver halide photographic emulsion is enhanced by a sulfur compound, a reducing agent, a noble metal or a polyalkylene oxide compound. However, these sensitizing methods increase the fogging tendency as well as the photographic sensitivity. Therefore, various anti-fogging agents are added to photographic emulsions.
Typical examples of anti-fogging agents are 4-hydroxy-6-methyl-1,3,3a,7-tetrazaindene and 1-phenyl-5-mercaptotetrazole. The former compound markedly suppresses the increase of fogging of light-sensitive materials or photographic emulsions during storage. However, this compound exhibits only a small anti-fogging effect in controlling fog immediately after the production of the light-sensitive material. On the other hand, the latter compound controls fog immediately after production. Therefore, favorable results are obtained by using these two compounds in combination.
However, when light-sensitive materials are processed at an elevated temperature, 4-hydroxy-6-methyl-1,3,3a,7-tetrazaindene does not exhibit a marked fog controlling effect, while 1-phenyl-5-mercaptotetrazole, when used in a sufficient amount to control fog, deteriorates the sensitivity so seriously that the use of this compound is not practical.
Thus, in elevated temperature development, it has been difficult to control fogging sufficiently using the aforesaid anti-fogging agents to the same extent as in ordinary development (e.g., conducted at about 20.degree.C).